JP2019084158A5

JP2019084158A5 -

Info

Publication number: JP2019084158A5
Application number: JP2017215898A
Authority: JP
Filing date: 2017-11-08
Publication date: 2020-12-24

Description

上記目的を達成するための一手段として、本発明の画像処理装置は以下の構成を有する。すなわち、複数のエネルギーの放射線撮影により照射された前記複数のエネルギーの放射線が被写体を透過した複数の放射線画像を取得する画像取得手段と、前記複数の放射線画像の画素値に基づいて、前記複数の放射線画像の少なくとも１つの放射線画像に異常な画素が存在するか否かを検出する検出手段と、を有する。 As one means for achieving the above object, the image processing apparatus of the present invention has the following configuration. That is, based on the image acquisition means for acquiring a plurality of radiation images in which the radiation of the plurality of energies irradiated by the radiography of the plurality of energies has passed through the subject, and the pixel values of the plurality of radiation images, the plurality of radiation images. It has a detecting means for detecting whether or not an abnormal pixel is present in at least one radiographic image of the radiographic image.

Claims

An image acquisition means for acquiring a plurality of radiographic images in which radiation of the plurality of energies transmitted by radiography of a plurality of energies has passed through a subject .
A detection means for detecting whether or not an abnormal pixel is present in at least one radiographic image of the plurality of radiographic images based on the pixel values of the plurality of radiographic images.
An image processing device characterized by having.

The image acquisition means was obtained by high-energy radiography, which is a radiological image obtained by two types of energy radiography, which is a radiological image obtained by high-energy radiography, and low-energy radiography. Acquire a low-energy radiological image, which is a radiological image,
The detection means is based on the pixel values of the high-energy radiation image, the pixel values of the low-energy radiation image, and information about a predetermined substance that can be contained in the subject at the time of radiography, and the high-energy radiation. The image processing apparatus according to claim 1, wherein it detects whether or not the abnormal pixel is present in either the image or the low-energy radiographic image.

The detection means obtains each of the pixel value of the high-energy radiographic image and the pixel value of the low-energy radiographic image from the effective atomic number of a substance that can be contained in the subject at the time of photographing and the two types of energy. The image processing apparatus according to claim 2, wherein when the pixel value is not included in the range of the pixel values to be obtained, the presence of the abnormal pixel is detected.

In the detection means, each of the pixel value of the high-energy radiographic image and the pixel value of the low-energy radiographic image is a pixel obtained from the thickness of a substance that can be contained in the subject at the time of photographing and the two types of energy. The image processing apparatus according to claim 2, wherein when the value is not included in the range, the presence of the abnormal pixel is detected.

The image acquisition means is a radiographic image obtained by radiography of three types of energy, that is, the high-energy radiographic image, the low-energy radiographic image, and the radiation of energy between the high-energy and the low-energy. Obtain a medium-energy radiographic image, which is a radiological image obtained by imaging,
In the detection means, each of the pixel value of the high-energy radiographic image, the pixel value of the medium-energy radiographic image, and the pixel value of the low-energy radiological image is the thickness of a substance that can be contained in the subject at the time of photographing. The image processing apparatus according to claim 2, wherein when the energy is not included in the range of pixel values obtained from the three types of energies, the presence of the abnormal pixels is detected.

The invention according to any one of claims 2 to 5, further comprising a calculation means for calculating the ratio of the pixel ratio of the high-energy radiographic image to the pixel value of the low-energy radiographic image for each pixel. The image processing apparatus described.

The detection means has a line attenuation coefficient when the substance that can be contained in the subject at the time of photographing is irradiated with the high energy radiation and a line attenuation when the substance is irradiated with the low energy radiation. The image processing apparatus according to claim 6, further comprising detecting the presence of the abnormal pixel when it is not included in the range of the ratio with the coefficient.

A substance information conversion means that converts the pixel ratio into substance information that identifies a substance that can be contained in the subject at the time of shooting.
A substance information correction means for correcting the substance information in the abnormal pixel detected by the detection means, and
The image processing apparatus according to claim 6 or 7, further comprising.

The image processing according to claim 8, wherein the substance information correction means corrects the substance information in the abnormal pixel by using the substance information in pixels adjacent to the abnormal pixel in the spatial direction. apparatus.

The substance information correction means according to claim 8 or 9, wherein the substance information correction means corrects the substance information in the abnormal pixel by using the substance information in pixels adjacent to the abnormal pixel in the time direction. Image processing device.

The image processing apparatus according to any one of claims 8 to 10, wherein the substance information is an effective atomic number corresponding to the substance or a thickness of the substance.

The image acquisition means was obtained by high-energy radiography, which is a radiological image obtained by two types of energy radiography, which is a radiological image obtained by high-energy radiography, and low-energy radiography. Acquire a low-energy radiological image, which is a radiological image,
For each pixel, a calculation means for calculating the ratio of the pixel values of the high-energy radiographic image and the low-energy radiographic image, and
The ratio is the minimum value of the ratio between the line attenuation coefficient when a substance that can be contained in the subject at the time of photographing is irradiated with the high energy radiation and the line attenuation coefficient when the substance is irradiated with the low energy radiation. The first aspect of claim 1, further comprising a determination means for determining whether or not abnormal pixels are present in the high-energy radiographic image or the low-energy radiographic image by comparing with the maximum value. Image processing device.

The image processing according to claim 12, further comprising an abnormal pixel correction means for correcting pixel values of the high-energy radiographic image and the low-energy radiographic image based on the determination result by the determination means. apparatus.

The image acquisition means further acquires a medium energy radiographic image, which is a radiographic image obtained by radiography of energy between the high energy and the low energy.
The calculation means calculates at least two pixel ratios of the pixel value of the high-energy radiation image, the pixel value of the medium-energy radiation image, and the pixel value of the low-energy radiation image for each pixel.
The determination means sets the ratio of the two pixels to a line attenuation coefficient when the substance that can be contained in the subject is irradiated with the high energy radiation and a line when the substance is irradiated with the low energy radiation. By comparing the minimum and maximum values of the ratio with the attenuation coefficient, it is determined whether or not abnormal pixels are present in the high-energy radiographic image, the medium-energy radiographic image, or the low-energy radiographic image. The image processing apparatus according to claim 12, wherein the image processing apparatus is used.

A claim characterized by further comprising an abnormal pixel correction means for correcting pixel values of the high-energy radiographic image, the medium-energy radiographic image, and the low-energy radiographic image based on the determination result by the determination means. Item 14. The image processing apparatus according to Item 14.

The image processing according to claim 13 or 15, wherein the abnormal pixel correction means corrects a pixel value in the abnormal pixel by using a pixel value in a pixel adjacent to the abnormal pixel in the spatial direction. apparatus.

The image processing according to claim 13 or 15, wherein the abnormal pixel correction means corrects a pixel value in the abnormal pixel by using a pixel value in a pixel adjacent to the abnormal pixel in the time direction. apparatus.

Further having a substance information conversion means for converting into substance information about a substance that can be contained in the subject at the time of shooting.
The calculation means further calculates the ratio of the pixel values of the image corrected by the abnormal pixel correction means as the corrected pixel ratio.
The method according to any one of claims 13 and 15 to 17, wherein the substance information conversion means converts the corrected pixel ratio into substance information regarding a substance that can be contained in the subject at the time of shooting. Image processing device.

The image processing apparatus according to claim 18, wherein the substance information is an effective atomic number corresponding to the substance or the thickness of the substance.

An image acquisition step of acquiring a plurality of radiographic images in which radiation of the plurality of energies transmitted by radiography of a plurality of energies has passed through a subject, and
A detection step of detecting whether or not an abnormal pixel is present in at least one of the plurality of radiographic images based on the pixel values of the plurality of radiographic images.
An image processing method characterized by having.

It has a phosphor that converts radiation into light and a detector that detects light.
An image acquisition means for acquiring a plurality of radiographic images in which radiation of the plurality of energies transmitted by radiography of a plurality of energies has passed through a subject .
A radiography apparatus comprising: a detection means for detecting whether or not radiation that has not been converted into light by the phosphor has been incident on the detector based on pixel values of the plurality of radiographic images. ..

It is a control method of a radiography apparatus having a phosphor that converts radiation into light and a detector that detects light.
An image acquisition step of acquiring a plurality of radiographic images in which radiation of the plurality of energies transmitted by radiography of a plurality of energies has passed through a subject, and
A detection step of detecting whether or not radiation that has not been converted into light by the phosphor has been incident on the detector based on the pixel values of the plurality of radiation images.
A method for controlling a radiography apparatus, which comprises.

A program for causing a computer to function as the image processing device according to any one of claims 1 to 19.

A program for operating a computer as the radiographing apparatus according to claim 21.